1901.] OjS" THE PTEKTLOSIS OF THE GIANT HUMMING-BIRD. 311 



Two specimens from the foot oF Gunong Inas : one, very young. 

 1 caught running on the trunk of a tree, the other, a female, on 

 the ground ; its dimensions are : — 



Length of head 11 mm. 



„ body 35 „ 



„ tail 75 „ 



,, fore limb 20 „ 



,, hind limb 20 „ 



Breadth of head 5 „ 



I have much pleasure in naming this species after Mr. Stanley 

 riower, to whose work on the Reptilian fauna of the Malay 

 Peninsula I am much indebted. 



Lygosoma chalcides (Linn.). 



Li/ffosoma cJialcides, Bouleuger, Cat. Liz. iii. p. 340 ; S. S. Flower, 

 P.Z.S. 1899, p. 652. 



Malay name, " Ular Berkaki " or legged snake. 



Specimens were collected at Ban Kong Eah in Pataluug and at 

 Khota Bhara, Eaman. The natives regard it as the youag of 

 Typhlops or CyliiidropMs, and say that its legs gradually grow 

 smaller and smaller until they finally disappear. 



3. On the Pterylosis of the Giant Humming-bird (Paiagona 

 gigas). By Professor D^Arcy Wentworth Thompson, 

 C.B., F.Z.S. 



[Eeceived April 2, 1901.] 



(Text-figures 77-82.) 



Our knowlege of the pterylosis of the Humming-birds is ex- 

 tremely scanty. It is based mainly on Nitzsch's very brief notes, 

 supplemented by some observations of Dr. Shufeldt's. Nitzsch's 

 very elementary figures are the only ones that I am acquainted 

 with. The following account is based on the examination of a 

 spirit-specimen of Paiagona received lately by the Museum of 

 University College, Dundee, from Mr. Alexander liodger of the 

 Perth Museum. 



The Pterylosis or the Head. 



The feathering of the head may be most simply described as 

 starting backwards from the base of the bill in three lateral lines 

 and a median ventral one. The three lateral lines start respectively 

 (a) from the base of the upper mandible, above the nasal flap or 

 cover ; (b) from the neighbourhood of the nostril below the level of 

 its cover; (c) from below the gape parallel to the line of the jaw. 



The upper lateral band (a), corresponding to the fronto- parietal 

 area of Pycraf t, forms a closely feathered triangle (text-fig. 77, 

 fr.tr.) over and behind the nasal valve, after which it narrows so 

 as to leave a moderately wide space in front of and over the eye ; 

 then, the interspaces between its feathers becoming much wider, 



21* 



